Jett Hamilton Roberts was born at 4:20 PM on April 20, a rep for the singer confirmed to the mag.
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Little Jett weighed in at 7 lbs., 8 oz.
"At one point I was trying to gain weight for the role, and I noticed I had put on 7 lbs. in 7 days. And I thought, my god! What's going on here," she told the mag in January. "I thought something was wrong with me, and I found out I was pregnant the day I was supposed to leave for Africa."
Filming while pregnant posed a variety of challenges for the expecting mom.
"That was one of the biggest challenges of my life. First trimester! You're sick every morning. It was seven hours time difference, the heat, the bugs, the 14 hour days," she told the mag. "[But,] my doctors gave me a clean bill of health and said you can do this, so I did it."
Jill and Lil John have been reportedly dating since 2007. The couple announced their plans to marry in June.
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